super late reply but Ive been researching temp control units, as far as I can tell people that had the bbqguru dx2 dx 3 with pit viper motor upgraded to fireboard 2 without purchasing a new blower. Apparently it works better with the fireboard 2 as it limits voltage to the motor instead of on-off full rpm pulses that the bbq guru does.
The pit viper 10 cfm motor has more than enough air to keep a wsm going , anything bigger seems like overkill for that size smoker.
I havent pulled the trigger yet but the fireboard 2 drive with a pit viper motor seems like an option Im interested in, I am also looking at the flameboss 500 and guru dx3....the fireboard 2 with pit viper came up slightly less $$$ than the 500...